Hitachi YUTAKI M R32 Series - Page 76

76
PMML0600 rev.0 - 06/2022
6
OPTIONAL UNIT WIRING FOR ACCESSORIES
ELECTRICAL AND CONTROL SETTINGS
◆ Aquastat for circuit 1
Aquastat is a security accessory to control in order to prevent high water temperature entering
into oor system (Circuit 1). This devices must be connected to terminals 22 & 23 for circuit 1.
When this devices is activated because of the high temperature of the water, it stops the water
pump in order to stop the ow of water to the heating oor.
Terminals 22 and 23 are jumped if there is no Aquastat connected. In case of setting an
installation with Aquastat, remove the jumper between terminals 22 and 23 of the Terminal
board 2 and connect the Aquastat as shown in the following picture.
22 23
Jumper
22 23
C
Second Aquastat
1
Circuit 1 (for WP)
Output terminals (Default output functions)
◆ Mixing valve for Circuit 2
The mixing valve is controlled to maintain the second heating temperature at the second heating
temperature set point. The control system decides how much to open or close the mixing valve
to achieve the desired position of the valve.
24 25 26
M
(C)
(O)
(N)
Brown
Black
Blue
Mixing Valve
(Circuit 2)
Terminal
Name
Description
24
C
Close
25
O
Open
26 N Neutral
Valve requirements:
Power supply: 230V AC 50Hz
Maximum running current: 100mA